1. Field of the Invention
The present invention relates to an electrophoretic display device that displays images using electrophoresis.
2. Discussion of the Related Art
An electrophoretic display device (EPD) refers to a device that displays images using electrophoresis in which colored charged particles are moved by an external electric field. Since the electrophoretic display device has bistability, even though the applied voltage is removed, the original image can be maintained for a long time. In other words, the electrophoretic display device can maintain a certain picture screen for a long time even though a voltage is not continuously applied thereto. Accordingly, the electrophoretic display device is suitable for the field of e-book, which does not require quick switching of the screen. Also, the electrophoretic display device is advantageous in that it does not dependent upon a viewing angle unlike a liquid crystal display device and provides picture images comfortable to the eyes at a similar level to those of papers.
FIG. 1 is a brief view illustrating an electrophoretic display device according to the related art.
Referring to FIG. 1, the electrophoretic display device 100 according to the related art includes a first substrate 110 provided with a common electrode (not shown), a second substrate 120 provided with a thin film transistor (TFT) array (not shown), and an electrophoretic film 130 arranged between the first substrate 110 and the second substrate 120.
The electrophoretic film 130 includes a plurality of microcapsules 131. Each of the microcapsules 131 contains (i) a dielectric solvent 1311, (ii) black particles 1312 dispersed in the dielectric solvent 1311 and charged with positive, and (iii) white particles 1313 dispersed in the dielectric solvent 1311 and charged with negative. If an electric field is applied to the black particles 1312 and the white particles 1313, the black particles 1312 and the white particles 1313 are moved inside the dielectric solvent 1311 by Coulomb's force, whereby picture images are displayed.
The electrophoretic display device 100 according to the related art, however, has a problem in that the manufacturing cost is increased due to use of the expensive electrophoretic film 130. In this respect, a new electrophoretic display device that does not require such an electrophoretic film 130 would be beneficial.